James k



'UNITED STATES PATENT- oFFrcE. i

JAMES K. HowE, or NEW YORK, N. Y.

f THEORY CONSTRUCTION OF VESSELS.

Specification of Letters Patent No. 5,771, dated September 19, 1848.

said improvement.

My improvement consists in' a method of giving to the outline orV external shape ofV the hull of the vessel or boat of whatever size may be required the form of arcs of cir-v cles in combination approaching or resembling elliptical lines, and of ellipses, under certain rules and relative proportions hereafter to be described; and these circles or ellipses are to be applied as well to the lateral shape and position of the sides or ribsof the vessel as to the shape of the underside or bottom of the vessel measuring on a line following the keel from stem to stern. In order to carry out vthis method, (taking one particular example for illustrati0n,) I

first take the exact length of the vessel re` quired upon a straight keel measured between two perpendiculars from stem `to stern, and in order to find a point which I call the center or central point upon said keel to work from I take'a point distant one third from the end of this line forward, and two thirds from the end aft, the one third forward being for the bows of the vessel, and the two thirds aft being for the after part and dead rise.Y This rule' of taking a central point to start from to form the hull of the vessel forward and aft isinvariable, and as will hereafter Ibe seen is the starting point in my discovery in any given length of vessel to be constructed. I next proceed to obtain the width or breadth of beam of the vessel over this central point, and the proper width or breadth of beam over this point for a vessel strictly according to my improvement, and taking a particular scale for illustration, is just one sixth of the lengt-h; and the depth of the hold between the keel line aforesaid and the deck or rather what I call the deck line, upon the same strict plan should be just'I one half of this, that is to say one twelfth the length 0f the vessel, It should be observed. that `the-deck may be placed in practice above or below this line which I call the deck line as Y set forth hereafter. I then proceed to obtain the curves for the ribs or side of the vessel.

fTo do this I take a vertical line from the central,` point upon the keel just described and extend that vertical line to a point disl ytant above the central point one half the :breadth or .one twelfth the length of the vessel', and I make this point the center of a circle, with this .vertical line for a radius;

land, the arc of the circle formed by this line lforfa radiusy will be the curve or arc re- `quired for the ribs of the vessel and her sides vertically.

Having thus given the method of obtaining the depthV of hold from the deck line to the upper surface of the lkeel at the central point aforesaid-'fand alsoithe breadth of.

beam above this centralpoint and the curve ofthe vessels ribs or sides vertically, I now.

proceed to obtain the form or shape of the lvessel longitudinally, following the underside or bottom of the vessel along the keel from stem to stern. And first to obtain the vcurve or dead rise forward of the abovementioned central point upon lthe line of thekeel: ythis must be formed also upon the arc of a circle to be obtained as follows:

Take for a center of this `circle a point verl i tical to the central point aforesaid in the keel line aforesaid and distant from it so far that a line .betweenthese two points for a radius will describe` an arc or circle 'the arc of which beginning at the central point upon the keel line aforesaid, shall, being extended pass. through a third point f' dis-v tant from this vertical line or radius one4` third the length of the vessel forward, and

at the height above the line ofthe keel aforesaid of one twelfth the length of the vessel, or in other words sol thatthis arc will pass through a point in the deck line above described forward' distant one thirdk the vessels length from the vert1cal line l justdescribed for a radius, and vertical to` the keel line, this point being the point of the stem or forward end of the vessel." Upon'the keel or into it with this. are 0rV curve for its rise and the dead rise forward are to be placed the ribs, the keel rising according to this curve for this purpose,the

said ribs being placed or arranged accord" :ing t@ a rule hereinafter to be described.' It

will beobserved that the curves of the ribs or sides of the vessel vertically at the central point havin" beenv obtained' in' ther'nan-w ner before descrl ed, all the ribs or standing side timbers for the whole length of the vessel fore and aft from stem to stern are to be of this same arc or curve so that every part of the bottom and sides of the hull' looking horizontally 'o'f the VX'fe's'sel Shall have' the same curvature, and but one curve of rib `will be required throughout the whole length of the vessel.-

WThe neit thing to be determined is the rise of the vessel upon the keel abaft the vcentral point, or the dead 'rise aft as Vit is f j cle or arc drawn with thisllinei forv a radius,

i t point upon the deck line at `the stern of thev 1V laid out the whole length of the vessel upon `square lines between perpendiculars may if the centerv being at the vertical point `at the end of the line and carried from the afore= said central point aft in continuation of the curve or arc forward will pass through a Vessel which will be "distant from the-cem tral line of radius along the deck line in the same plane as the circle' two: thirds the length of the vessel;

-V Upon this 'curve between the central point and the point last mentioned at the stern the keel is to be raised andv formed and the 'ribs are to be set into the keel upon the same curve. The combination'l of the two arcs of circlesand the continuation of their curves` r ure twice the distance' upon the keel line aft the centralpoint for the same amount of dead risse-that is to say if your keel or 'dead rise rises oneinch f'or one foot measured on the keel line forward, it must rise but one inch for every two feet measured `on the-keel line aft the central point this proportion of measurement is 'not strictly and perfectly exact, and would produce a slight variation from the true curve line aftI in vessels of considerable length;V to be perfectly accurate i the curve lipe must be Ystrictly followed. It

is next to be observed that theV ribs are tot` be set into 'the dead rise'o keell in such a man:

ner that they shall all point to the center of th-e circle the arc of which forms the dead rise fore or aft as they are fore or aft ofthe central point respectively: this it will be ,the ribs if of thesame length as the central r'ib Ior nearly"` so willv necessarily rise up toiward the bows and stern above the deck line according as thecurve for dead rise at bows `or stern rises. These upper ends of the ribs are vto'be cut `off asfthey rise at such point 'above the deck line asmay be requiredfor bulw'a-rks, so that a line rvdrawn along their =ends whenv so cut olf will be level or in the `same level plane or nearly soi the shear o1 rise of bulwarks howeverV may be varied.'

The planking of the vessel may be placed "over the ribs or sides v'of the vessel in the .usual manner; f i

The keel which I- have described above as actually so made in practice be afterward cut away and shaped to suit the shape or dead rise of theves'sel as may be required. A vHaving thus described the inethod of building the hull of a vessel upon one particular scale 'or rule of m'y'discovery and improvement nowl proceed to further illustrate this by reference tothe drawings.

In Figure 1,- the line BAA represents the keel line of the length of the vessel required between the perpendiculars J A and C B; the line E E E between C and J is the deck line; the line H I is the line of the rib tops or' endsektending above the deck line and forming the bulwarks above the deck line J C; O is the central point in the keel Alin-e one third of the length of the keel line `from A J and two thirds from B C; the line between F and O is the radius of the circle `forming the curve of the bows or dead rise forward; F J is the radius of the same circle touching the deck line at J land O J is the arc or curve. The line O F, the radius. of the circle for the bows bei-ng extended between three and f'ouil times its length to Gr making the vertical line G F O, constitutes the radius for the circle or are for the dead rise Qaft between 'O C producing a rise aft. the

central' point as nearly'as possible one half `for the saine distance of the r'is'e forward'of the central point.l VThe ribs are shown by the numerals from 1 to 30. The yinclination of the ribs toward the centers of the respective circles forming the curve of the bows and stern is shown by the variation from the vertical dotted lines 1, 7, 13, 25, 30. The line O K shows the depth from deck line to keel line at the central point. The curve C O J Shows the entire shapeof the hull on the keel line and the dead rise fore and aft; The circles L L L L L L show 'the curve of the ribs and the points where they are cut olf and what height or portion of the arc is left when cut off to a level with the top of the central rib at the points indicated by the dotted lines running from these circles to the ribs 7 18, 20, 25, 30. In these circles the continuous black lines show thev exact length of the arc constituting the ribs at the points just referred to by the numbers, 7, 18, 20,` 25, 30, the points where the continuous black lines meet in the circles L L L L L L being all on the Vsame level. The breadth of the vessel at these `points is also shown by the space between the points where the ribs are cut 0H". Y

Having thus set forth the method of shaping the hull according to the particular -scale above set forth, I now proceed to describe how my discovery and improvement is to be-applied to vessels whose hulls are required of greater or less depth of hold or greater or less width of hold at the bottom,

or greater or less curve of dead rise `following the line of the keel fore and aft. This system is susceptible of everyv variety of form in its application to the hulls of vessels butalways preserving the relative proportion fore and aft of the central point in the curve of the line of the keel above set forth, and also always making the curves of the ribs through the whole length of the vessel the same, or upon the same parts of circles; so as to make every part of the water line of the vessel the same and carrying out the application of the arc of the circle or circles combined through her sides and shape below externally from bows to stern, so that there shall be no straight line or surface in the outline'.

If it be required to build a vessel of a given length but of a more moderate dead rise fore and aft, the points D C through which the circles fore and aft are to pass from O, are to be lowered so as yto make the circles largerv as in Fig. 2. The line C, O, D

represents the bottom curve t-he radius off the arc C O being between three and four times in length that of the radius of the arc O D, the length of the vessel in Fig. 2, being the same as that in Fig. 1, but the curve of the bottom fore and aft and of they ribs or sides very different,

`When it is required to give the vessel an increased. area of bearings on her sides, or

to have her width or flattening of bottom greater than would result from the form of thecircle given by the rule above laid down inthe first part of the specification, it will be necessary, to carry out my system, of elliptical curves or arcs of circles or of both combined, to adopt the following method or rules. Take a line equal to the width or breadth of beam of the vessel at the deck lineover t-he central point O. Divide this line into two equal parts and let these parts of the line when so divided be the horizontal diameters of twovcircles touching each other (as in Fig. 2 at L L L L &c.). The curves of these circles will be the curve for the ribs of the vessel for a certain length upon the sides. Then to get the curve for the bottom of the vessel or lower portion of the ribs in connection with and continuation of the arcs orsegments of those circles7 a larger circle must be drawn the curve of which shall touch externally t-he lower curves of the two circles just mentioned but must never cut them as is shown in Fig. 2, L1, L2, L3, L4,

in continuation forming a'curve approaching the curve of an ellipse, and that part of the curve .of the greater circle which touches the two lesser ones, is tobe taken for the curve for the remaining part of thev ribs required, the arcs of the three circlestogether in combination forming a curve yresembling 4an elliptical curve, and constituting the Vcurve or shape of rib or sides of the vessel throughout. ,Take iny Fig. 2, L4 the two smaller circles of which are `formed upon two diameters equal together to the width of the vessel. The larger circle with radiusequal to the two diameters of the smaller circles represented by the dottedV lines, c, c, 0 strikes the outer lower curves of t-he two smaller circles at l c andthe arc of the larger circle between these two vtouchingpoints d e` is the curvel for the bottom of the kvessel or lower part of the rib.

When it is required to have the vessel of a still .greater width in proportion to the depth, or to have the bottom still more` shallow and spreading two `circles are to be drawn as before; their two diameters united, however, being less than the width of the vessel, so that their arcs shall not be cut by the are of the greater circle to be drawn for the curve of the bottomthese circles re then tobe so far apart that the space e- .tween them together with their diameters united shall equal the width of the yvessel over the central point on the deck line, and

so that the larger circle to be drawn as before so as to touch the points corresponding to CZ e, will be the curve in continuation with the smaller circles for the sides, the three arcs or segments together forming vthe entire rib. All the ribs fore and aft are to L5, L6,the arcs of the two circles together on nearly an even line having three lift-hs of the circle above the keel or keel line for the bulwarks which hence curve slightly inward, Y

the height of these however may be varied. The curves and form of these sections of ribs, cut off as they rise at part-icular points when they are set into the keel are shown in Fig. 2 at L1, L2, L3, L", L5, L, their tops being on an even line and being set into the keel on the curve line C O D at the points indicated by the lower extremity of the dotted lines m1, m2, m3, m4, m5.

It will be seen by experiment that these methods of forming the entire ribs for the vessels sides are capableiof every degree of variation within any given length or length and width, preserving at the same time in every variation the principle of the curved lines of the circle or `ellipse or both combined throughout the whole lower fexternal shape of the vessel.

lVith regard to themethod of obtaining the arcs of the circles" required in actual practice it may be done in any way most convenient either by the use of a line or cord for a radius or by using the dividers upon a scale adapted to their powers and then measuring the circles and parts ofV circles and adapting them in proper proportions to the large scale required.

The keel of .a vessel her hull or bottom being constructed as above, will stand out at a pretty sharp angle to the Vvessels bottom, which in a large vessel for ocean navigation would be inconvenient as oifering too straight a surface upon the side of the keel to the action and force-of the waves. The angle between the dead wood and bottom may be carried out or filled by an easy line formed by taking a section of the arc of one of the smaller circles used for the curves of the ribs, and placing it reversed on eitherside of the dead wood, as at ai, 5,10, in Fig. 3; in Fig. 3, b represents the bottom of the keel at the stern; a, c the bottom of the vessel, a b c b the filling up of the angle by the reversed section or arc of the circle. There the space between the keel and bottom aft is carried o-ut or filled as just described, the space between the keel and bottom forward, must also be carried out or filled in the same manner, so as to preserve even or equal bearings fore and aft; but it is to be observed that this filling out both fore and aft must be continued from the central point O beginning with nothing at that point and gradually widen ing toward the stern and bows upon a curve beginning at the said central point and being the curve or arc of a circle somewhat larger than that forming the curve of dead rise aft and forward respectively, so that an easy line will be produced; but the filling out forward may in some cases be dispensed with.

The position of the rudder should be somewhat different from the common mode. The rudder is to be hung in the same plane as the keel but obliquely so that the lower part shall be hung farther forward` (the keel being beveled of for that purpose) than the upper part so that when the helm is turned, the rudder will not turn upon a vertical axis, but one considerably oblique. The operation of the rudder hung in this manner tends to lift the stern of the vessel when putting about and causing her to turn quicker and easier.

The bottom or line of dead rise of the vessel may also be obtained by lines composed of ellipses by taking the same point O for a center or starting point, and making the dead rise aft that point of an ellipse whose larger (or transverse) axis shall be equal to twice two thirds the length of the vessel, and whose' shorter (or conjugate) axis shall be equal to twice the depth of the vessel; and

A*for the dead rise forward of the central point an ellipse whose larger (or transverse) axis shall be equal to twice one third the lengthV of the vessel, and its shorter (or conjugate) axis the same as that of the other ellipse. These two ellipses divided at their shorter axes and the half o-f the two joined together at their shorter axes so that their longer axes may be in one and the same straight line, will form the dead rise for the whole length of the vessel and her shape underneath from stem to stern, the form of the ribs also may be that of an ellipse produced by taking for the curve of rib over or at the central point the outline of ellipse produced by taking for one axis the width of the vessel and for the other axis twice the depth of holdall the other ribs to be of the same form: the ribs in this case are to be set in -their places upon the line of dead rise, their planes being perpendicular to the line of dead rise, and as they rise upon lit are to be out off to suit the sheer of the vessel required, the central rib should however always rise to three fifths of its diameter, as it should also in cases where the rib is obtained of circles.

The combination and arrangement of vcurves as above described in all the various proportions or ligures which may be required for the length, breadth, depth, curvature of bottom and sides, &c., for thevessely required I believe to be upon a principle conformable to mathematical or geometrical truths or principles strictly, and they pro-` forms of creatures whose element vis the rately in outline with that of the hump-V backed whale which is a fish of great speed.

It follows from the foregoing system that the hulls of vessels produced according to it present no straight lines or surfaces whatever to the water but everywhere horizontally and vertically are curves, a thing which I believe has never before been attained in ship building. Another result is that their sides must always exactly correspond with each other, which has not before been attained with entire accuracy. A further effect is that the sides being throughout their length upon thesamecurve, or rather equal curves, when the curve of the central rib is obtained all the others may be cut or sawed to correspond, doing away with the necessity of molds and of laying 0H upon the molding floor in a great measure, and producing a great reduction in the expense of building by the ordinary method, as well as saving of labor, &c. Also further, a vessel built in this manner owing to the shape of the ribs and manner of setting them upon the keel their planes pointing to centers, will be of greater strength and power to resist the action of heavy seas, and will present also an easy surface so that their force will be much less felt and the waves more easily turned aside. Further the vessel will sail faster and nearer to the wind than vessels built inthe usual manner and will also be more stanch and steady; it will also come about quicker and easier when sailing on a wind; the proportions are also extremely beautiful and perfect.

Vith regard to the constructing the keel of the vessel, it may be observed that its construction both as to the parts where the ribs touch the line of dead rise and the other parts is the same as that used in ordinary ship building, and so with other parts of the vessels hull so far as is consistent with the principles or mode of construction above set forth.

It may be proper to observe that the length of the respective radii of the circles of the dead rise fore and aft may be obtained with accuracy by the following rules obtained mathematically.

In all sizes of vessels built according to my plan the length of the radius of the curve of deadrise forward may be accurately obtained by the following rule: Add the square of the depth to the square of one third the length of the vessel and divide the sum thus obtained by vtwice the depth; the quotient will betherequired radius..V '.Thus for` example 1n F ig.l l, tolnd the radius kF O`:

Given the length ofthe vessel J 0:6 inches;

given the depth ofithewvessel K inch. I-Ience I` i 2%) T the required radiusA in inches. The reason of this rule may be learned from the following mathematical solution founded on Fig. l;

Upon examination it will be seen that this last equation is the mathematical form of expressing the rule above laid down.

Again, in all sizes of vessels built according to my plan the length ofthe radius of the curve of the dead rise aft may be accurately obtained by the following rule: Add the square of the depth to the square of two thirds the length of the vessel, and divide the sum thus obtained by twice the depth; the quotation will be the required radius. Thus for example in Fig. l, to find the radius GO: Given the length of the vessel JCIG inches; given the depth of the vessel KO= inch. Hence the required radius in inches. The reason of this rule may be learned from the following mathematical solution founded on Fig. l:

GOzGC.

G02: (GO-KO) 2-|-KC.2

last equation is the mathematical formof expressing t-he rule last above laid down.

What I claim as my discovery and improvement, and desire to secure by Letters Patent, isf The method herein made known of determining the configuration of vessels of all sizes, by describing the outline of the bottom or what I call the dead-rise by two arcs of unequal circles or ellipses which meet on the upper edge of the keel (which is their common tangent) at what I call the central Upon examination it will be seen that this point, in combination with curves or arcs incidng with planes radiating from the cenof circles, or ellipses described as aforesaid ters of the circles, or elli ses, of which the and forming the out-line of the ribs, all the curves of the dead rise are segments. ribs in the same Vessel, being segments of the JAMES IQ HOWE.

5 same curve, and set upcnor along the curve In the presence of* of the dead rise,V fore and aft, the-trans'- JOHN B. STAPLES, verse pla'n in which the ribs are placed co- ROBERT PIKE. 

